Sprinkler head



Jan. 3U, A' C. ROWLEY 1,945,459

SPRINKLER HEAD Filed Jan. ll, 1933 Patented Jan. 30, 1934 UNITED STATES SPRINKLER HEAD Y Arthur C. Rowley, Drexel Hill, Pa., assigner to Globe Automatic Sprinkler Company, Philadelphia, Pa., a corporation of Pennsylvania Application January 11, 1933. Serial No. 651,191

3 Claims. (Cl. 169 138) This invention relates to sprinkler heads for automatic fire-extinguishing systems, and a principal object of the invention is to provide a generally improved and substantially tamper-proof sprinkler head.

Another object of the invention is to simplify the construction and to reduce the cost of manufacture of sprinkler heads of the type involved.

More specifically, an object of the invention is to provide a sprinkler head. having novel and simplified means for retaining the closure cap seated under pressure.

In the attached drawing:

Figures 1 and 2 are front and side elevational views of a sprinkler head made in accordance with my invention;

Fig. 3 is a longitudinal sectional view of the strut member;

Fig. 4 is an end view of the strut assembly, and

Fig. 5 is a section on the line 5 5, Fig. 3.

With reference to the drawing, my improved sprinkler head comprises a frame 1 having a threaded hollow base 2 and arms 3, 3 extending from opposite sides of the base 2, said arms converging beyond the end of the base and uniting at 4 to form, in effect, a yoke. As shown in Fig. 1, those portions of the arms 3, 3 adjoining the base 2 are outwardly bowed to thereby permit elongation by iiexure of the yoke in the direction corresponding to the longitudinal center line of the hollow base portion 2. While the particular form illustrated is well adapted for this purpose, it is obvious that other forms of yoke could be used.

The threaded portion of the base 2 adapts the frame for attachment in the sprinkler system, and the opposite open end of the base 2 is normally closed and sealed by a cap 5, this cap being held to its seat by means in the present instance of a strut 6, which in accordance with my invention is conned between the said cap and the outer end of the yoke 3 4. In the present instance, I have shown the strut 6 as consisting of a plurality of spheres 7 held in end-toend relation within a tubular casing formed in the present instance-as shown in Figs. 3, 4 and 5, of inner and outer split cylinders 8 and 9. The sections of the respective cylinders are united by means for example of a fusible metallic alloy or solder, and the spheres are retained in the inner cylinder by similar fusible material which fills the interstices between the inner cylinder walls and the spheres, as shown in Fig. 3. A strut of this general character is illustrated and claimed in my copending application Serial Number 631,427.

It will be noted that the terminal spheres 7 of the strut project beyond the ends of the tubular casing, and in assembly engage respectively in recesses formed in the cap 5 and in the outer end of the yoke 3 4. In order to retain the cap 5 securely to its seat and to insure a proper release under abnormal temperature conditions, it is necessary that the strut 6 be placed under pressure, and this is accomplished in the present instance through the natural resiliency of the frame and specifically of the arms 3, 3. As previously set forth, these arms are formed to permit flexure, and consequent elongation of the yoke. The bronze generally used in the manufacture of sprinkler heads of this type is satisfactory for the purpose. Following elongation of the yoke by pressure suitably applied, the strut 6 may be slipped into place, and when the yoke is subsequently released, the strut is placed under the required pressure, insuring maintenance of the cap 5 in position'and a proper and prompt release of the strut under abnormal temperature conditions.

Heretofore it has been customary to employ a. screw threaded into the outer end of the yoke and carrying the deflector 10 for forcing the strut against the cap 5. With this system, it is diflicult to place the strut 6 of the various sprinkler heads under4 any predetermined uniform pressure, and since the screw is a releasable element, the device may be more or less readily tampered with. By the present invention, the screw is entirely eliminated and the inherent resiliency of the frame employed to retain the closure cap in position. Since the frames and struts may readily be made uniform, a substantially uniform capseating pressure necessarily results. Since considerable pressure must be applied to stretch the frame sufficiently to permit insertion or removal of the strut, the sprinkler head is substantially tamper-proof, and there is substantially no possibility of change in the pressure conditions within the device of a character that might adversely affect the operating characteristics.

Since the usual adjusting screw has been eliminated by the present invention, the deflector 10 is secured directly to the outer end of the yoke, and the means whereby this is accomplished may vary widely. There may also, as suggested above, be considerable modification in the general form of the particular head frame and of the strut without departure from the invention.

lll)

I claim:

1. A sprinkler head comprising an integral frame, a closure cap and a seat for said cap in the frame, and thermally-releasable means interposed between the cap and an opposed portion of the frame and holding the cap to its seat, said holding means being insertable into operative position in the frame by distortion of the latter and said frame being adapted for said distortion to admit the holding means, the inherent resiliency of the frame thereby tending to exert pressure through said holding means to force the cap against its seat. l

2. A sprinkler head comprising an integral frame consisting of a hollow base member and a. yoke extending from one end of said base member, a closure cap for an end of said base member, said yoke being resilient and adapted for elongation under pressure to permit insertion of a thermally-releasable strut between the said cap and an oppositely positioned surface of the yoke, a. thermally-releasable strut insertable in said frame only by elongation of said yoke as set forth whereby when the yoke is released the inherent resiliency Ythereof acts through the strut to exert pressure upon the cap, and means for normally preventing displacement of the strut.

3. A sprinkler head comprising an integral frame, a closure cap and a seat for said cap in the frame, thermally-releasable means conned in said frame and holding the cap to its seat, said frame being resilient and distortable to permit adjustment of said holding means to the operative position in the frame, andV said holding means being of a character permitting said insertion only after the said frame has been distorted and normally retaining the frame in the distorted condition.

ARTHUR C. ROWLEY. 

